Free resources only from the GL context thread.
Bug #3179882

Resources were freed following garbage collections on a worker thread.
This worker thread had no EGL context, which would cause the renderer
to incorrectly assume that the memory was liberated.

Change-Id: Ifdb51f94ddf42641e8654522787bfac532976c7c
diff --git a/libs/hwui/utils/GenerationCache.h b/libs/hwui/utils/GenerationCache.h
index 2e76236..42e6d9b 100644
--- a/libs/hwui/utils/GenerationCache.h
+++ b/libs/hwui/utils/GenerationCache.h
@@ -130,7 +130,7 @@
 
 template<typename K, typename V>
 V GenerationCache<K, V>::getValueAt(uint32_t index) const {
-    return mCache.valueAt(index);
+    return mCache.valueAt(index)->value;
 }
 
 template<typename K, typename V>